Double lock standing seams or double standing seams in metal roofs are formed as rectangular reentrant bends in edges of overlapping metal sheets. The seams stand about one inch or more above the plane of the sheets, and the rectangular reentrant bends occupy about an upper one-half inch of the seams.
Connectors to connect objects, for example snow guards, to the roof have grooved bodies for spanning the seams. Threaded openings in one side of the groove receive screws. The opposite side has spheroid internal recesses for receiving and holding portions of the seams that are pushed into the recesses by the screws. The screws should be tightened sufficiently to distort and hold the seams using powered wrenches or hand operated wrenches. When torqued sufficiently for the screws to deform the metal of the seam into the spheroid recesses and thus prevent dislodgment of the snow guard from the seam, the screws acting through the seam and recesses may distort inferior bodies causing them to crack or split. When the screws are tightened insufficiently, the mounts may slide along or off the seams, causing possible damage to the roof or objects below.
Fasteners historically have been perpendicular to the seam and parallel with the plane of the roof surface or panel and have made for difficult installations due to their close proximity to the panel, leaving little room for either hand or electric impact tools. Additionally, the sight line of the installer is impeded by the close proximity to the roof panel surface. As such installer frustration and roof panel damage are common in the trade.
Needs exist for improved metal seam mounts.